Yujie Xia1, Daniel W Pack. 1. Department of Chemical and Biomolecular Engineering, University of Illinois, 600 S. Mathews Avenue, Urbana, Illinois, 61801, USA.
Abstract
PURPOSE: Pulsatile delivery of proteins, in which release occurs over a short time after a period of little or no release, is desirable for many applications. This paper investigates the effect of biodegradable polymer shell thickness on pulsatile protein release from biodegradable polymer microcapsules. METHODS: Using precision particle fabrication (PPF) technology, monodisperse microcapsules were fabricated encapsulating bovine serum albumin (BSA) in a liquid core surrounded by a drug-free poly(lactide-co-glycolide) (PLG) shell of uniform, controlled thickness from 14 to 19 μm. RESULTS: When using high molecular weight PLG (Mw 88 kDa), microparticles exhibited the desired core-shell structure with high BSA loading and encapsulation efficiency (55-65%). These particles exhibited very slow release of BSA for several weeks followed by rapid release of 80-90% of the encapsulated BSA within 7 days. Importantly, with increasing shell thickness the starting time of the pulsatile release could be controlled from 25 to 35 days. CONCLUSIONS: Biodegradable polymer microcapsules with precisely controlled shell thickness provide pulsatile release with enhanced control of release profiles.
PURPOSE: Pulsatile delivery of proteins, in which release occurs over a short time after a period of little or no release, is desirable for many applications. This paper investigates the effect of biodegradable polymer shell thickness on pulsatile protein release from biodegradable polymer microcapsules. METHODS: Using precision particle fabrication (PPF) technology, monodisperse microcapsules were fabricated encapsulating bovineserum albumin (BSA) in a liquid core surrounded by a drug-free poly(lactide-co-glycolide) (PLG) shell of uniform, controlled thickness from 14 to 19 μm. RESULTS: When using high molecular weight PLG (Mw 88 kDa), microparticles exhibited the desired core-shell structure with high BSA loading and encapsulation efficiency (55-65%). These particles exhibited very slow release of BSA for several weeks followed by rapid release of 80-90% of the encapsulated BSA within 7 days. Importantly, with increasing shell thickness the starting time of the pulsatile release could be controlled from 25 to 35 days. CONCLUSIONS: Biodegradable polymer microcapsules with precisely controlled shell thickness provide pulsatile release with enhanced control of release profiles.
Authors: Amy C Richards Grayson; Insung S Choi; Betty M Tyler; Paul P Wang; Henry Brem; Michael J Cima; Robert Langer Journal: Nat Mater Date: 2003-11 Impact factor: 43.841
Authors: Hok Hei Tam; Mariane B Melo; Myungsun Kang; Jeisa M Pelet; Vera M Ruda; Maria H Foley; Joyce K Hu; Sudha Kumari; Jordan Crampton; Alexis D Baldeon; Rogier W Sanders; John P Moore; Shane Crotty; Robert Langer; Daniel G Anderson; Arup K Chakraborty; Darrell J Irvine Journal: Proc Natl Acad Sci U S A Date: 2016-10-04 Impact factor: 11.205